Voltammetric Determination of Rhodamine B Using a ZIF-67/Reduced Graphene Oxide Modified Electrode
Huỳnh Trường Ngọ, Vo Thang Nguyen, Tran Duc Manh, Trần Thanh Tâm Toàn, Nguyen Thi Minh Triet, Nguyễn Thanh Bình, Nguyễn Thị Vương Hoàn, Tran Vinh Thien, Đinh Quang Khiếu
Abstract
In the present article, the synthesis of zeolite imidazolate framework-67/reduced graphene oxide (ZIF-67/rGO) and voltammetric determination of Rhodamine B (RhB) are demonstrated. The obtained materials were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption/desorption isotherms. It was found that the ZIF-67/rGO composite consists of ZIF-67 nano-particles highly dispersed on the rGO matrix and possesses a high specific surface area. Because of the synergistic effect of good conductivity of rGO and high surface area of ZIF-67, the ZIF-67/rGO—modified glassy carbon electrode exhibits good electrochemical behavior toward Rhodamine B (RhB) oxidation. The use of this electrode to quantitate RhB with differential pulse voltammetric method was successful with a broad linear range, from 0.96 to 44.07 μ g.L -1 of RhB and a low limit of detection of 1.79 μ g.L -1 . The procedure was able to be applied to quantitatively determine RhB content in several food samples with an exceptional recovery rate (98-103%). The quantitative results highly agreed with that provided by high-performance liquid chromatography, revealing that this material is promising in in situ monitoring of other illegal additives in food.